Re: [xml-dev] Re: determining ID-ness in XML

[David Brownell <david-b@pacbell.net>]

Mike Champion asked:
>     Could the
> xml+id processor be actually layered on top (or in front of) an  XML 1.0
> processor without changing the DTD validation logic?

I think validation (DTD, any of the various schemas, etc) hasn't been
raised in this context before ... ID uniqueness is an obvious thing to test,
but I'm less sure IDREF/IDREFS attributes should be expected to point
to these.  What should validating these attributes mean?

I think it'd be most natural to test validity of "xml:idatts" after DTD or
schema-du-jour rules (like an application level validity test), so as not
to demand needless changes to other specs. With SAX I'd expect such
errors to be reported by some component using ErrorHandler.error(),
just like any other validity error.

Of course, that still permits updated DTD/schema-du-jour/... processing
to integrate xml:idatts processing.  But it eliminates confusion about where
in the processing chain such tests go -- and resolve issues like whether
WFness is affected (no), and whether declaration is needed (yes).

- Dave